Yolanda Foster’s battle with Lyme disease, will be a hot topic on Season 6 of The Real Housewives of Beverly Hills. In a new interview with HuffPost Live on Monday, Nov. 30, Kyle Richards spoke out about her costar’s health struggles.

“I want to be very clear about this,” Richards, 46, prefaced. “She 100 percent has Lyme disease and is really suffering. There’s no question about that at all, so I really want to be clear about that, because there have been people thinking I doubted or questioned it because of a comment made in which I was discussing the trailer for the upcoming season.”

Last week, in an exclusive sneak peek of the upcoming season of the hit Bravo show, Lisa Vanderpump discussed Foster’s illness with Richards, saying, “I don’t quite understand what’s wrong with her. I don’t know if it is Lyme disease, but I’m not criticizing her. I’m just questioning it.”

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Foster, 51, also discussed her battle with the disease in the trailer, saying, “It’s been a long journey. I look quite normal, but yet I’m so sick. I have weakness in my legs, no brain function. I mean, I haven’t driven a car in three years.”

“She’s definitely very sick, and struggling every day to hold on,” Richards told HuffPost Live, adding that her costars’ suspicions began with the extravagant treatments that Foster was receiving.

Richards also spoke out about another RHOBH star — her sister Kim Richards, who was arrested in August after she was caught shoplifting over $600 worth of items from a Target store in San Fernando Valley, Calif.

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Kyle said that Real Housewives helped Kim, 51, “in the long run,” and that coming back to the show will be “a good thing” for her.

“She’s taking care of herself, so that’s all that matters now,” Kyle said of her older sister.

Watch Kyle Richards’ full interview with HuffPost Live to see her discuss Kris Jenner’s birthday bash and more about The Real Housewives of Beverly Hills.

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